The present invention relates to a scroll wheel of a mechanical mouse, especially to a magnetic scaling and positioning scroll wheel of a mechanical mouse in which at least one scaling-and-positioning portion arranged at a scaling-and-positioning member and one of a plurality of magnetic division portions disposed on a circular scaling-and-positioning surface are magnetically attracted to each other correspondingly. Thereby users can operate and rotate the scroll wheel more precisely.
A computer mouse provides various basic functions including inputting coordinates, clicking objects, or scrolling horizontally, etc. Refer to FIG. 1 and FIG. 2, take a conventional mechanical/ball mouse 100 as an example. A housing of the ball mouse 100 includes a top cover 101, a bottom cover and a side surface 103. A left button 104, a right button 105 and a projecting middle scroll wheel 106 are arranged at a front side of the top cover 101. According to users' needs, at least one button 107 having other functions and called hot key is disposed on the top cover 101 and/or side surface 103. The left and the right buttons 104, 105, the scroll wheel 106 or the button 107 is a common input device of the ball mouse. As to other electronic or mechanical components of the ball mouse 100, such as mechanical or optical rotary encoder, roller and support of the wheel, circuit board, etc., they are mounted in the housing. The arrangement of the electronic and mechanical components can be achieved by the techniques in the field available now.
While in use, users operate the scroll wheel 106 by their fingers so that a mechanical or optical rotary encoder on a rear end of a rotating shaft of the scroll wheel 106 outputs coded pulse signals generated along with scale divisions of an encoding disk therein when the scroll wheel 106 is rotated. The ball mouse 100 used now, a general/normal rotation mode of the scroll wheel 106 is under control of the scrolling angle or turning angle of the user's finger pressed on the scroll wheel. When the users turn the scroll wheel 106 a certain central angle (or a portion of the circumference), the scroll wheel 106 is rotated the central angle (or a bit larger) synchronously and then stopped when the user's finger stops the operation. In the general/normal rotation mode, a corresponding scroll distance is generated on the screen by the encoding disk of the rotary encoder. This is the common page scroll mode. However, the ball mouse needs other operation mode while being applied to computer games or contests. Not only the operation speed of the mouse should be increased (such as user's fingers can press and activate each key (or hot key) quickly, the precision in rotating the scroll wheel also needs to be improved. For example, the scroll wheel can be scaled and positioned by user's fingers precisely during rotation. Thus the mouse cursor can be positioned for selecting and moving on the screen.
Yet the scaling of the rotation of the scroll wheel of the conventional ball mouse is not obvious for users. Users can't easily intuit the rotation distance of each scale division on the encoding disk of the rotary encoder. The users are unable to operate the scroll wheel precisely and not sure how far they are scrolling. Thus the mouse cursor can't be positioned in time while selecting and moving element on the screen. This causes trouble and inconvenience in computer games or contests while selecting the elements on the screen.
Moreover, there are some prior arts that reveal certain magnetic devices disposed on scroll wheels of the ball mouse such as U.S. Pat. No. 8,040,331 and US Pub. App. No. 2009/0096750A1. Refer to U.S. Pat. No. 8,040,331, a dual-mode rotatable input device revealed includes a biasing mechanism having a magnet and configured to urge the movable interface member into engagement with the resistive surface for control of a rotational velocity of the rotatable member (such as a scroll wheel). Thus the magnet is not used for scaling and positioning of the rotation of the scroll wheel. The complicated design of the structure is not suitable for mass production. Refer to US Pub. App. No. 2009/0096750A1, a scroll wheel device is disclosed. The major characteristic of the present invention lies in the adoption of electromagnetic means to translate the spin of a wheel module into continuous electrical signals. A permanent magnet is incorporated in the wheel module to provide magnetic field. Two sensors tangential to the spinning direction of the permanent magnet are used to detect the variations of the magnetic field from the spin of the wheel module in accordance with the Hall Effect. In this prior art, the magnetic device is also not used for magnetic scaling and positioning of the scroll wheel during rotation.